How can you arrange these 10 matches in four piles so that when you move one match from three of the piles into the fourth, you end up with the same arrangement?
What happens to the area of a square if you double the length of the sides? Try the same thing with rectangles, diamonds and other shapes. How do the four smaller ones fit into the larger one?
Have a go at this 3D extension to the Pebbles problem.
In how many ways can you fit two of these yellow triangles together? Can you predict the number of ways two blue triangles can be fitted together?
If you split the square into these two pieces, it is possible to fit the pieces together again to make a new shape. How many new shapes can you make?
This challenge involves eight three-cube models made from interlocking cubes. Investigate different ways of putting the models together then compare your constructions.
How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?
What is the smallest cuboid that you can put in this box so that you cannot fit another that's the same into it?
In this town, houses are built with one room for each person. There are some families of seven people living in the town. In how many different ways can they build their houses?
Move four sticks so there are exactly four triangles.
A toy has a regular tetrahedron, a cube and a base with triangular and square hollows. If you fit a shape into the correct hollow a bell rings. How many times does the bell ring in a complete game?
Hover your mouse over the counters to see which ones will be removed. Click to remove them. The winner is the last one to remove a counter. How you can make sure you win?
A dog is looking for a good place to bury his bone. Can you work out where he started and ended in each case? What possible routes could he have taken?
Take a rectangle of paper and fold it in half, and half again, to make four smaller rectangles. How many different ways can you fold it up?
How many different triangles can you make on a circular pegboard that has nine pegs?
What is the best way to shunt these carriages so that each train can continue its journey?
Can you shunt the trucks so that the Cattle truck and the Sheep truck change places and the Engine is back on the main line?
Swap the stars with the moons, using only knights' moves (as on a chess board). What is the smallest number of moves possible?
10 space travellers are waiting to board their spaceships. There are two rows of seats in the waiting room. Using the rules, where are they all sitting? Can you find all the possible ways?
Can you cover the camel with these pieces?
Here you see the front and back views of a dodecahedron. Each vertex has been numbered so that the numbers around each pentagonal face add up to 65. Can you find all the missing numbers?
What is the total area of the four outside triangles which are outlined in red in this arrangement of squares inside each other?
How many different ways can you find of fitting five hexagons together? How will you know you have found all the ways?
This task, written for the National Young Mathematicians' Award 2016, involves open-topped boxes made with interlocking cubes. Explore the number of units of paint that are needed to cover the boxes. . . .
Can you find ways of joining cubes together so that 28 faces are visible?
Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Find your way through the grid starting at 2 and following these operations. What number do you end on?
How can you arrange the 5 cubes so that you need the smallest number of Brush Loads of paint to cover them? Try with other numbers of cubes as well.
A hundred square has been printed on both sides of a piece of paper. What is on the back of 100? 58? 23? 19?
Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?
Can you work out how many cubes were used to make this open box? What size of open box could you make if you had 112 cubes?
What is the greatest number of counters you can place on the grid below without four of them lying at the corners of a square?
What is the least number of moves you can take to rearrange the bears so that no bear is next to a bear of the same colour?
Reasoning about the number of matches needed to build squares that share their sides.
Design an arrangement of display boards in the school hall which fits the requirements of different people.
Investigate the number of paths you can take from one vertex to another in these 3D shapes. Is it possible to take an odd number and an even number of paths to the same vertex?
A magician took a suit of thirteen cards and held them in his hand face down. Every card he revealed had the same value as the one he had just finished spelling. How did this work?
How many DIFFERENT quadrilaterals can be made by joining the dots on the 8-point circle?
When I fold a 0-20 number line, I end up with 'stacks' of numbers on top of each other. These challenges involve varying the length of the number line and investigating the 'stack totals'.
One face of a regular tetrahedron is painted blue and each of the remaining faces are painted using one of the colours red, green or yellow. How many different possibilities are there?
What are the next three numbers in this sequence? Can you explain why are they called pyramid numbers?
How will you go about finding all the jigsaw pieces that have one peg and one hole?
In each of the pictures the invitation is for you to: Count what you see. Identify how you think the pattern would continue.
Have a go at making a few of these shapes from paper in different sizes. What patterns can you create?
Move just three of the circles so that the triangle faces in the opposite direction.
Make a flower design using the same shape made out of different sizes of paper.
Can you visualise what shape this piece of paper will make when it is folded?
Can you find a way of counting the spheres in these arrangements?
Looking at the picture of this Jomista Mat, can you decribe what you see? Why not try and make one yourself?
Can you work out what shape is made by folding in this way? Why not create some patterns using this shape but in different sizes?